A frequently used curative for pneumatic tire sealant compositions is a quinoid type system, which generally comprises a quinoid and an activator. The activator, often described as a cocuring agent or "B" component, is used to achieve crosslinking in association with the dormant quinoid uniformly distributed as a curing agent into the elastomer or rubber (such blend being called an "A" component). The terms "elastomer" and "rubber" will be used interchangeably in this specification.
Traditionally, the quinoid rubber curing agent is solution compounded into the elastomer to form component A. This solution compounding usually achieves a uniform distribution of the curing agent in the elastomer. The quinoid curing agent is initially solubilized in an organic, polar solvent and then mixed with a rubber "masterbatch" (high molecular weight elastomer; low molecular weight tackifier; reinforcing agent; solvent). The various solvents are then removed to yield a uniform fine distribution of curing agent in elastomer ("component A") to form a dry blend for later crosslinking the elastomer once the curing agent and the co-curing agent come together.
While many solvent processes in rubber compounding are acceptable for current manufacturing techniques, the use of organic, polar solvents in rubber compounding presents the expected issues of solvent purchasing and storage costs before manufacture, solvent removal costs during manufacture, solvent capture costs as a byproduct of manufacture, and other manufacturing costs involved with the use of solvents. Moreover, most rubber vulcanization processes begin with Banbury-type mixing techniques which is a dry, solid mixing process. Thus, the presence of solvents to intimately mix various ingredients is temporary.